Southwest Carry-On Size: Bag Dimensions and Airline Rules

The Southwest carry-on size limit is 24 × 16 × 10 inches (61 × 41 × 25 cm), including wheels and handles. Passengers can bring one carry-on bag and one personal item on Southwest flights at no extra cost.

Compared with many U.S. airlines, Southwest allows slightly larger carry-on bags and does not enforce a strict carry-on weight limit, as long as passengers can lift the bag safely into the overhead bin. Most standard 20-inch carry-on suitcases fall within this limit, making them suitable for Southwest flights.

Southwest Carry-On Size Limit and Bag Allowance

Southwest Airlines allows passengers to bring one carry-on bag and one personal item for free. The carry-on bag must fit in the overhead bin, while the personal item should fit under the seat in front of you.

Southwest Carry-On Rules Overview

In addition to the carry-on luggage, passengers may also bring one personal item, which must fit under the seat in front of them.

Carry-On Luggage Size on Southwest

The maximum carry-on luggage size on Southwest is 24 × 16 × 10 inches (61 × 41 × 25 cm), including wheels and handles. This size limit ensures that carry-on bags can fit safely in the overhead bins on Southwest aircraft.

Unlike many airlines, Southwest does not enforce a strict weight limit for carry-on luggage. Passengers simply need to be able to lift the bag safely into the overhead bin without assistance.

Choosing a suitcase designed around common airline cabin dimensions, such as a 20-inch carry-on suitcase, usually helps ensure the bag fits comfortably within Southwest’s carry-on size limit.

Personal Item Size on Southwest

Southwest does not publish exact dimensions for personal items, but they must fit under the seat in front of you.

In practice, many travelers choose personal items around 16 × 13 × 8 inches or smaller, which typically fit under most aircraft seats. This size is widely considered a safe guideline for laptop bags, small backpacks, and purses.

Keeping personal items compact helps ensure they fit easily under the seat, which is the designated storage location for personal items during the flight.

What Bags Fit Within Southwest Carry-On Size Limits

Many types of travel bags can fit within Southwest’s carry-on size allowance. Passengers are allowed one carry-on bag and one personal item, so choosing the right combination of bags can help maximize packing space while staying within airline rules.

Carry-On Suitcases

A standard carry-on suitcase is one of the most common options for Southwest flights. Suitcases designed around 20–22 inches typically fit comfortably within most airline cabin limits.

For example, many 20-inch carry-on suitcases, including models like the Voyageur Carry-On 20'', are designed around common airline cabin dimensions, making them suitable for Southwest flights and short trips.

Travel Backpacks

Travel backpacks are another popular option because they are flexible and easy to store in overhead compartments.

Many travelers prefer backpacks for short trips or weekend travel because they are easier to carry through airports and can compress slightly to fit within airline size limits.

Duffel Bags

Duffel bags can also work as carry-on luggage if their dimensions stay within Southwest’s limits. Soft-sided duffel bags are especially convenient because they can compress slightly to fit into overhead bins.

However, travelers should always check the bag’s dimensions carefully, since some larger duffel bags may exceed the airline’s carry-on size allowance.

Personal Item Bags

In addition to a carry-on bag, Southwest allows passengers to bring one personal item that fits under the seat in front of them.

Common personal item bags include:

• Laptop bags
• Small backpacks
• Purses
• Camera bags

Choosing a compact personal item helps ensure it fits properly under the seat in front of you, which is the designated storage space for personal items during the flight.

Where Carry-On Bags Are Stored on Southwest Flights

Carry-on luggage must be stored properly during flights to keep the cabin organized and ensure passenger safety.

Overhead Bin Storage

Most carry-on suitcases and larger travel bags are stored in the overhead bins above passenger seats. Passengers should place their bags wheels-first or sideways, depending on the bin layout, to maximize available storage space.

Under Seat Personal Items

Smaller items such as purses, laptop bags, or small backpacks should be stored under the seat in front of you. Keeping personal items under the seat helps free up overhead bin space for larger carry-on luggage.

What Happens If Your Carry-On Is Too Large on Southwest

If a carry-on bag exceeds Southwest’s size limit, airline staff may require the bag to be checked at the gate before boarding.

This process is known as gate-checking, where the bag is placed in the aircraft's cargo hold and returned at baggage claim after landing.

Southwest has traditionally allowed two checked bags per passenger, so gate-checking a carry-on usually does not result in additional fees as long as you stay within the airline’s checked baggage allowance.

However, gate-checking can still be inconvenient if your bag contains travel essentials such as electronics, documents, or medications. To avoid this situation, travelers should measure their carry-on luggage before arriving at the airport.

Southwest Carry-On Size Compared With Other Airlines

Southwest’s carry-on size allowance is slightly larger than that of many other major U.S. airlines. While most airlines limit carry-on bags to around 22 × 14 × 9 inches, Southwest allows bags up to 24 × 16 × 10 inches, including wheels and handles.

Because Southwest allows slightly larger dimensions, travelers may find it easier to pack standard carry-on luggage or slightly larger cabin suitcases on Southwest flights.

However, overhead bin space can still vary depending on the aircraft type and how full the flight is. Choosing a compact carry-on suitcase designed around common airline cabin dimensions, like the Luminous Textured Carry-On 18''/20'', can help ensure the bag fits comfortably across different airline carry-on size limits.

Tips for Traveling With Carry-On Luggage on Southwest

Following a few simple tips can make traveling with carry-on luggage on Southwest easier and more convenient.

Choose the Right Carry-On Size

Select a carry-on bag designed to meet common airline luggage size limits. Many travelers prefer suitcases around 20 inches, which provide enough packing space for short trips while still fitting easily in overhead bins.

Pack Efficiently for Overhead Storage

Efficient packing helps maximize the available space inside your carry-on luggage. Rolling clothing, using packing cubes, and separating electronics can make it easier to access important items during travel.

Arrive Early for Better Overhead Space

Southwest uses an open seating boarding system, meaning passengers board in groups rather than assigned seats.

Because of this system, overhead bin space can fill up quickly on full flights. Boarding earlier improves your chances of storing your carry-on suitcase near your seat.

Conclusion

Southwest Airlines allows a carry-on bag up to 24 × 16 × 10 inches, along with one personal item stored under the seat. This carry-on allowance is slightly more generous than many other U.S. airlines, making it easier for travelers to bring standard carry-on luggage.

For example, many 20-inch carry-on suitcases, including models like the Voyageur Carry-On 20'', are designed around common airline cabin dimensions, making them suitable for Southwest flights and short trips. Choosing a properly sized bag, packing efficiently, and boarding early can help ensure your carry-on fits comfortably in the overhead bin and makes your Southwest travel experience smoother.

FAQ

Is Southwest strict about carry-on size?

Southwest is generally reasonable about carry-on size, but bags must still fit within the 24 × 16 × 10 inch limit and fit inside the overhead bin.

Can I bring a backpack and carry-on on Southwest?

Yes. Southwest allows one carry-on bag and one personal item, such as a backpack, purse, or laptop bag.

Does Southwest measure carry-on bags?

Southwest may ask passengers to place bags in a sizing bin at the gate if a bag appears too large. If it does not fit, the bag may need to be checked.

Are there weight limits for carry-on bags on Southwest?

Southwest does not enforce a strict weight limit for carry-on bags. Passengers only need to be able to lift the bag safely into the overhead bin.

Can a 24-inch suitcase be a carry-on on Southwest?

In most cases, no. Most 24-inch suitcases are designed as checked luggage and exceed Southwest’s carry-on size limit of 24 × 16 × 10 inches when wheels and handles are included.

Travelers who want to use a carry-on bag on Southwest usually choose 20-inch or 21-inch carry-on suitcases, which are more likely to fit in overhead bins.